Nanobiotechnology: Applications in Chronic Wound Healing.

Wounds occur when skin integrity is broken and the skin is damaged. With progressive changes in the disease spectrum, the acute wounds caused by mechanical trauma have been become less common, while chronic wounds triggered with aging, diabetes and infection have become more frequent. Chronic wounds now affect more than 6 million people in the United States, amounting to 10 billion dollars in annual expenditure. However, the treatment of chronic wounds is associated with numerous challenges. Traditional remedies for chronic wounds include skin grafting, flap transplantation, negative-pressure wound therapy, and gauze dressing, all of which can cause tissue damage or activity limitations. Nanobiotechnology - which comprises a diverse array of technologies derived from engineering, chemistry, and biology - is now being applied in biomedical practice. Here, we review the design, application, and clinical trials for nanotechnology-based therapies for chronic wound healing, highlighting the clinical potential of nanobiotechnology in such treatments. By summarizing previous nanobiotechnology studies, we lay the foundation for future wound care via a nanotech-based multifunctional smart system.

Tailored Hydrogel Delivering Niobium Carbide Boosts ROS-Scavenging and Antimicrobial Activities for Diabetic Wound Healing.

The treatment of diabetic wounds remains challenging due to the excess levels of oxidative stress, vulnerability to bacterial infection, and persistent inflammation response during healing. The development of hydrogel wound dressings with ideal anti-inflammation, antioxidant, and anti-infective properties is an urgent clinical requirement. In the present study, an injectable thermosensitive niobium carbide (Nb2 C)-based hydrogel (Nb2 C@Gel) with antioxidative and antimicrobial activity is developed to promote diabetic wound healing. The Nb2 C@Gel system is composed of Nb2 C and a PLGA-PEG-PLGA triblock copolymer. The fabricated Nb2 C nanosheets (NSs) show good biocompatibility during in vitro cytotoxicity and hemocompatibility assays and in vivo toxicity assays. In vitro experiments show that Nb2 C NSs can efficiently eliminate reactive oxygen species (ROS), thus protecting cells in the wound from oxidative stress damage. Meanwhile, Nb2 C NSs also exhibit good near-infrared (NIR) photothermal antimicrobial activity against both Staphylococcus aureus and Escherichia coli. In vivo results demonstrate that Nb2 C@Gel promotes wound healing by attenuating ROS levels, reducing oxidative damage, eradicating bacterial infection under NIR irradiation, and accelerating angiogenesis. To summarize, the Nb2 C@Gel system, with its ROS-scavenging, photothermal antimicrobial and hemostatic activities, can be a promising and effective strategy for the treatment of diabetic wounds.

Thermosensitive Hydrogel Incorporating Prussian Blue Nanoparticles Promotes Diabetic Wound Healing via ROS Scavenging and Mitochondrial Function Restoration.

Diabetic foot ulcer is a serious complication in diabetes patients, imposing a serious physical and economic burden to patients and to the healthcare system as a whole. Oxidative stress is thought to be a key driver of the pathogenesis of such ulcers. However, no antioxidant drugs have received clinical approval to date, underscoring the need for the further development of such medications. Hydrogels can be applied directly to the wound site, wherein they function to prevent infection and maintain local moisture concentrations, in addition to serving as a reservoir for the delivery of a range of therapeutic compounds with the potential to expedite wound healing in a synergistic manner. Herein, we synthesized Prussian blue nanoparticles (PBNPs) capable of efficiently scavenging reactive oxygen species (ROS) owing to their ability to mimic the activity of catalase (CAT), peroxidase (POD), and superoxide dismutase (SOD). In the context of in vitro oxidative stress, these PBNPs were able to protect against cytotoxicity, protect mitochondria from oxidative stress-related damage, and restore nuclear factor erythroid 2-related factor 2 (NRF2)/heme oxygenase-1 (HO-1) pathway activity. To expand on these results in an in vivo context, we prepared a thermosensitive poly (d,l-lactide)-poly(ethylene glycol)-poly(d,l-lactide) (PDLLA-PEG-PDLLA) hydrogel (PLEL)-based wound dressing in which PBNPs had been homogenously incorporated, and we then used this dressing as a platform for controlled PBNP release. The resultant PBNPs@PLEL wound dressing was able to improve diabetic wound healing, decrease ROS production, promote angiogenesis, and reduce pro-inflammatory interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) levels within diabetic wounds. Overall, our results suggest that this PBNPs@PLEL platform holds great promise as a treatment for diabetic foot ulcers.

Fascinating MXene nanomaterials: emerging opportunities in the biomedical field.

In recent years, there has been rapid progress in MXene research due to its distinctive two-dimensional structure and outstanding properties. Especially in biomedical applications, MXenes have attracted widespread favor with numerous studies on biosafety, bioimaging, therapy, and biosensing, although their development is still in the experimental stage. A comprehensive understanding of the current status of MXenes in biomedicine will promote their use in clinical applications. Here, we review advances in MXene research. First, we introduce the methods of synthesis, surface modification and functionalization of MXenes. Then, we summarize the biosafety and biocompatibility, paving the way for specific biomedical applications. On this basis, MXene nanostructures are described with respect to their use in antibacterial, bioimaging, cancer therapy, tissue regeneration and biosensor applications. Finally, we discuss MXene as a promising candidate material for further applications in biomedicine.

A novel salvianolic acid A analog with resveratrol structure and its antioxidant activities in vitro and in vivo.

E-DRS is a novel salvianolic acid A (SAA) analog, which was synthesized from resveratrol (RES) and methyldopate. Its structure is similar to that of SAA, but the 3',4'-dihydroxy-trans-stilbene group and the ester structure in SAA were replaced by the RES structure and an amine group, respectively. E-DRS scavenged free oxygen radicals effectively, including superoxide anion (ascorbic acid > E-DRS > SAA ≥ rutin > RES) and DPPH radical (rutin > E-DRS ≥ ascorbic acid > SAA > RES), and exhibited powerful total antioxidant capacity (ascorbic acid > E-DRS > SAA ≥ rutin > RES) in vitro. Furthermore, oral administration of E-DRS dose-dependently and significantly decreased CCl4 -induced oxidative stress in mice as indicated by the decreased content of hepatic malondialdehyde (MDA). In addition, oral administration of E-DRS also increased the content of nonenzymatic antioxidant glutathione (GSH) and the activity of antioxidant enzymes such as catalase (CAT) and superoxide dismutase (SOD) in the liver of mice. All these results demonstrated that E-DRS had good antioxidant activities both in vitro and in vivo, and could be a potential antioxidant agent after further optimization and evaluation.

[Diagnosis and endoscopic treatment of isolated sphenoid sinus disease].

OBJECTIVE: This study was to investigate the clinical symptoms, characterization of imaging technique and the effect of endonasal endoscopic surgery. METHOD: Following 38 cases of isolated sphenoid sinus disease patients, among whom 35 cases treated with nasal sinus CT (including 5 cases of MRI at the same time), 3 cases undergoing sinus MRI, 1 cases going through the CT cisternography. All patients underwent endoscopic sphenoid otomy, of which 33 cases underwent nasal olfactory cleft approach, 5 cases anterior ethmoid sinus and posterior ethmoid sinus approach (Messerklinger technology). RESULT: All patients were followed up for more than half a year, of which 34 were recoverd and 4 were improved. No obvious complications came up during or after endoscopic surgery. CONCLUSION: Isolated sphenoid sinus disease clinical symptoms are not typicaland without specialty; nasal examination had no positive sign, only with headache as the chief neurological symptom, often difficult to diagnose at an early stage. The CT and MRI are the best methods for the diagnosis of isolated sphenoid sinusitis. The nasal endoscopic operation is the preferred method for treatment of this disease.